document.write( "Question 369622: A test consists of 10 true-or-false questions. If a student randomly chooses answers for each question, find the probability that the student:
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document.write( "Answers at least 1 question correctly. (3 decimals) \r
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document.write( "I got 2^10 = 1,024 \r
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document.write( "I did this way, but does not work, very close... \r
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document.write( "C(10,1)/1024 = \r
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document.write( "10/1024 = .00976 \r
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document.write( "The answer is 0.999 but how? \r
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Algebra.Com's Answer #263393 by Fombitz(32388)![]() ![]() You can put this solution on YOUR website! Find the probability that the student answers none correctly. \n" ); document.write( "P(none)+P(not none)=1 \n" ); document.write( "P(not none)=1-P(none) \n" ); document.write( "So \"not none\" means he answer at least one correctly... up to and including all 10 correctly \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( "P(none)= \n" ); document.write( "P(not none)= \n" ); document.write( "P(not none)= \n" ); document.write( " \n" ); document.write( " |